Heat-treating container



Patented Jan. 19, 1926.

UNITED STATES PATENT OFFICE.

` RUDQLP RILINTEBMANN, or DETROI'I, MICHIGAN, `assew ro meinen 'emmces'rmes COMPANY, or hmmm MICHIGAN, A conrom ron or ienem` HEAT-TBEATINGCON N B Application med May '5, 1924. serial No. 71,2"7o.

To all whom `it may concerm Be is known that I, RUDOLPH F. FLINTEb MANN,a citizen of theUnited States of America, residing at Detroit, in theCounty 5 of Wayne and 'State of Michigan, have invented certain 'new anduseful Improvements in Heat-Treating Containers, g of which thefollowingis a specification, reference being had thei-ein to the accompanyingdrawings. v

The invention relates to heat treating containers and more particularlyto a carbonizing box adapted for long service at high temperatures. e v

The object of the invention is to provide a container or box so designedthat, when cast of heat resisting alloy metal, it will not warp or crackas a result of alternate exposure to high temperature and cooling toroom temperature. Alloy metals, dependent on a major peroentage ofchromium, nickel,

or silicon, for resistance to the oxidizing ef feet of hightemperatures, fail most frequently by cracking or warping out of shape.'This invention, by preventing or minimizing cracking and warping,prolongs the life of the container or box and reduces the cost per hourof service.

These and other objects have been accomplished in the present instanceby using the Construction as hereinafter set forth.

In the drawings:-

Figure l is a perspective View of my improved heat treating container;

Figure 2 is a longitudinal section thereof on the line 2 2 of Figure 3;

Figure 3 is a horizontal section on the line 3-3 of Figure 3;

F igure 4 is a sectional elevation of a modified Construction;

Figure 5 is another modified Construction having corrugations on thebottom surface thereof.

My improved heat treating cuntainer is made by casting in sand molds analloy which is of such composition that it resists `oxidation atelevatecl temperature. It has long been a matter of general knowledgethat the heat resistance of iron can be increased by the addition ofsilicon, chromium, or nickel, either singly or' together. At the presenttime several alloys are being 'freedom 'from sharp corners dissipatesthe forces of expansion and contraction so that enough strain to producea crack cannot be localized at one point. By elimination of cracking andwarpage as a cause of failure,-

my improved design of heat treating container increases the life' andvalue of heat resisting alloys. r

The improved design provides side walls entirely free from sharp cornerswhile they are rendered more rigid by stifl'ening corrugations. Thus, asshown in Figures 1 to 3, the container comprises the bottom wall 1 andthe side walls 2 integrally cast therewith, the side Walls being for-medwith a series of vertical corrugations 3 having smooth outcr and innercontours 'free from sharp corners. The side walls 2 are preferably ofuniform thickness throughout the entire periphery of the container andare united with the bottom wall l by the rounding portions 4. Thecontainer is provided With the feet or supporting runners 5 integrallycast with the bottom wall, and as shown in F igure 2 these feet may belocated at the corners of the box and extend diagonally inwardtherefrom. It will, of course, be understood that the feet or supportingrunners may be placed at any other desired oints on the bottom of thebox or container to fit a particular furnace design, 'or example, byhaving theni extend the entire length or width of the box.

In Figure 2 the corrugations are shown as terminating short of thebottom wall l and extending to the top surface of the container, whilein F igure 4 the corrugations are extended to intersect with the bottomwall. Figure 5 shows still a further modification having the bottomsurface 6 provided with longitudinal corrugations 7.

With each of these constructions the container is formed as an integralstructure of a cast heat resistant alloy, and the side Walls haveuninterrupted vertical corrugations entirely free from sharp cornerswhere the stresses set up by the temperature changes might be localizedto produce cracking or warping.

What I claim as my invention is 1. A heat treating container comprisinga cast structure of a heart resisting alloy having integral bottom andside walls, the side walls being formed with uninterrupted verticalcorrugations forming a wavy surface free from straight portionsintermediate said corrugations, the entire surface of said containerbeing free from sharp corners.

2. A heat treating container comprising a cast structure of a heatresisting alloy having integral side walls and a bottom wall orming asubstantially rectangular structure open at the top, the side wallsbeing formed with unnterrupted vertical corrugatons forming a wavysurface free from straight portions intermediate said corru ations.

3. cast heat treating container fol-med of a heat resisting alloy, saidcontainer comprising side walls and a bottom wall forming asubstantially rectangular structure o en at the top, the side wallsbeing forme( with uninterrupted vertical corrugations imparting to thewalls a waivy surface free from straight portions intermediate saidcorrugations, feet de ending from said bottom wall, said verticaicorrugations extending to the top of said eontainer.

'4. A hem: treatng container comprising a cast structure having integralbottom and side Walls, the side walls being forned with uninterruptcdvertical corrugations inparting a wvy' surface thercto free fromstraight portions, said structure being composecl of a sand east alloycontaining iron and a substantial amount of chromium sufficient torender the container resistant to oxidation at elevated ten'peratures.

In testimony whereof I aifix my signature RUDOLPH F. FLINTERMANN.

